A class of equivalent enhanced assumed strain and hybrid stress finite elements

Abstract

The interrelation of a certain class of finite elements based either on the Enhanced Assumed Strain (EAS) concept or the Hybrid Stress (HS) method is addressed. It is shown that both concepts lead to identical elements, if the material law is strongly satisfied in the Hu-Washizu principle. Conditions for the spaces of admissible functions are derived and the equivalence of the resulting weak formulations is proved. A `recipe' for the selection of trial functions of corresponding elements is given, and a class of equivalent EAS- and HS-elements is presented.